U.S. patent number 5,285,510 [Application Number 07/990,527] was granted by the patent office on 1994-02-08 for fiber optic connector.
This patent grant is currently assigned to The Whitaker Corporation. Invention is credited to Paul Slaney.
United States Patent |
5,285,510 |
Slaney |
February 8, 1994 |
Fiber optic connector
Abstract
A fiber optic connector resists signal interruption with a
structure that has an inner body, that receives and mounts an
optical fiber, and that has an outer body having an axial passage
that receives the inner body. The outer body has two sections
arranged in axial succession. The outer-body back section mounts a
captive element for mechanical coupling with a further optical
device with which the connector mates. The forward, second section
of the outer body is arranged for limited axial displacement
relative to the first section. The connector has structure forming
two springs or like resiliently acting elements; one biases the
front end of the inner body axially forward relative to the back of
the outer body, and the second biases the front of the outer body
forward relative to the back section of the outer body.
Inventors: |
Slaney; Paul (Groton, MA) |
Assignee: |
The Whitaker Corporation
(Wilmington, DE)
|
Family
ID: |
25536251 |
Appl.
No.: |
07/990,527 |
Filed: |
December 15, 1992 |
Current U.S.
Class: |
385/78; 385/56;
385/76; 385/84; 385/60; 385/66 |
Current CPC
Class: |
G02B
6/3821 (20130101); G02B 6/3891 (20130101); G02B
6/3887 (20130101) |
Current International
Class: |
G02B
6/38 (20060101); G02B 006/26 (); G02B 006/38 () |
Field of
Search: |
;385/53,56,60,62,66,69,70,72,76,77,78,81,84,86,87,88 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
AMP Incorporated "Fiber Optic Products" Catalog No. 82188 issued:
Feb. 1992, pp. 54,56,60-63..
|
Primary Examiner: Healy; Brian
Attorney, Agent or Firm: Lahive & Cockfield
Claims
What is claimed is:
1. In a fiber optic connector for optically coupling an end face of
an optical fiber to a further optical device or fiber, the
connector having a front end, a back end, and a captive element for
mechanical coupling with the further optical device, and being
arranged for supporting the optical fiber along an axis extending
between the connector front and back ends, the improvement
comprising
A) an inner body having axially spaced front and back ends and
having an axially extending through passage for receiving and
mounting the optical fiber with selected alignment,
B) an outer body
i) having axially spaced front and back ends, and having first and
second sections in axial succession between said ends, with said
second section forming said outer-body front end,
ii) said outer body having means for securing the captive element
to said first section,
iii) said outer body having a first axially extending through
channel for receiving said inner body for axial movement relative
to said first section along the axis,
C) means forming first resiliently acting means for resiliently
biasing said front end of said inner body axially forward relative
to said back end of said outer body, and
D) means forming second resiliently acting means for resiliently
biasing said front end of said outer body axially forward relative
to said first section of said outer body, whereby
whereby said inner body can be displaced axially relative to said
outer body first section in response to a compressive engagement on
said inner-body front end.
2. In a connector according to claim 1, the further improvement in
which said first resiliently acting means includes a first spring
element engaged between said inner-body and said outer-body first
section.
3. In a connector according to claim 2, the further improvement in
which said first spring element is a coil spring.
4. In a connector according to claim 1, the further improvement in
which said first resiliently acting means is normally stressed, and
becomes increasingly stressed as said inner body is axially
displaced toward said outer-body back end.
5. In a connector according to claim 1, the further improvement in
which said outer-body first section has a first radial shoulder,
and said inner-body has a second radial shoulder axially opposed to
said first radial shoulder, wherein said first resiliently acting
means is compressively engaged between said opposed shoulders.
6. In a connector according to claim 1, the further improvement in
which said outer-body second section includes tubular collar means
disposed concentrically around said inner body.
7. In a connector according to claim 1, the further improvement in
which the forward end of said outer-body second section is axially
movable backward relative to said outer-body first section in
response to engagement on said second section, and said second
resiliently acting means is increasingly stressed in response to
the backward movement.
8. In a connector according to claim 7, the further improvement in
which said second resiliently acting means is normally stressed and
becomes increasingly stressed as said outer-body second section is
axially displaced toward said outer-body back end.
9. In a connector according to claim 8, the further improvement in
which said outer-body first section has a third radial shoulder,
and said outer-body second section has radial flange means axially
opposed to said third shoulder, and wherein said second resiliently
acting means is compressively engaged between said opposed flange
means and said third shoulder.
10. In a connector according to claim 9, the further improvement in
which said outer-body first section has a fourth radial shoulder,
arranged for contacting said flange means when said outer-body
second section is displaced to a forward position, for limiting the
forward axial displacement of said outer-body second section.
11. In a connector according to claim 1, the further improvement in
which said outer-body first and second sections are separate parts
and said second resiliently acting means includes a second spring
element engaged between said outer-body first and second
sections.
12. In a connector according to claim 11, the further improvement
in which said second spring element is a coil spring.
13. In a connector according to claim 1, the further improvement in
which said inner body has a radial shoulder and said outer-body
second section has a radial shoulder disposed axially opposed to
said inner-body shoulder for limiting the forward axial
displacement of said inner body.
14. In a connector according to claim 1, the further improvement in
which said second resiliently acting means is normally stressed
when the connector is disconnected from the further optical
device.
15. In a connector according to claim 14, the further improvement
in which said second resiliently acting means is increasingly
stressed when the connector is connected to the further optical
device.
16. In a connector according to claim 1, the further improvement in
which said outer-body second section is arranged to abut the
further optical device when the connector is coupled with the
further optical device.
17. In a connector according to claim 16, the further improvement
in which said outer-body second section is disposed, relative to
said outer-body first section, in a first axial position when the
connector is disconnected from the further optical device, and is
axially displaced backward, in opposition to a force of said second
resiliently acting means, to a second axial position when the
connector is mated with the further optical device.
18. In a connector according to claim 16, the further improvement
in which said outer-body second section includes means for biasing
the further optical device away from said connector back end when
the connector is coupled with the further optical device.
19. In a connector according to claim 1, the further improvement
comprising annular sealing means carried on said outer-body second
section and arranged for abuttingly contacting the further optical
device when the connector is coupled with the further optical
device.
20. In a connector according to claim 19, the further improvement
in which said sealing means is disposed concentrically around said
inner body.
21. In a connector according to claim 1, the further improvement in
which said outer-body second section is fixed to said outer-body
first section and is arranged to abut the further optical device
where the connector is coupled therewith.
22. In a connector according to claim 21, the further improvement
comprising resilient sleeve means forming, at least in part, said
outer-body second section, said sleeve means being arranged for
abuttingly engaging the further optical device when the connector
is coupled to the further optical device, and forming, at least in
part, said second resiliently acting means.
23. In a connector according to claim 1, the further improvement
comprising feeder tube means disposed along the axis within said
channel concentrically within said outer body, said feeder tube
having a front end attached to said inner-body back end and having
a back end proximal to said outer-body back end.
24. In a connector according to claim 23, the further improvement
in which said optical fiber is secured to said inner body by an
adhesive material, and said feeder tube confines said adhesive
material.
25. In a connector according to claim 1, the further improvement
comprising sealing means carried on at least one of said outer body
and the further optical device, said sealing means being disposed
to compressively abut said outer-body second section when the
connector is coupled with the further optical device.
26. In a connector according to claim 1, the further improvement in
which said inner-body front end is the connector front end.
27. A fiber optic connector for optically coupling an end face of
an optical fiber to a further optical element or fiber, said
connector comprising
A) a captive element for mechanical coupling with a further optical
device,
B) an inner body having axially spaced front and back ends and
having an axially extending through passage for receiving and
mounting the optical fiber with selected alignment,
C) an outer body
i) said outer body having a first through channel for receiving
said inner body for axial movement relative to said first section
along the axis,
ii) having axially spaced front and back ends, and having first and
second sections in axial succession between said ends,
iii) said outer body having means for securing said captive element
to said first section, and
iv) said second section forming said outer-body front end and being
relatively proximal to the connector front end, and being arranged
for selected backward axial displacement of said outer-body front
end, relative to said first section, from a first forward
position.
D) means forming first resiliently acting means for resiliently
biasing said front end of said inner body axially forward relative
to said back end of said outer body, and
E) means forming second resiliently acting means for resiliently
biasing said front end of said outer body axially forward relative
to said first section of said outer body.
Description
BACKGROUND
This invention relates to connectors for fiber optic cables. In
particular, the invention relates to an improved fiber optic
connector that allows quick connection and disconnection with
mating connectors, and that is resistant to signal
interruption.
Fiber optic communication cables typically include at least one
light transmitting optical fiber clad in an optically insulating
material. The cladding prevents dispersion of light out of the
optical fiber. The fiber optic cable usually has a protective
external buffer over the clad fiber, typically of a plastic
material, such as nylon, which may or may not be removed to
terminate the cable. Optical cables usually have an outer
protective layer, called a jacket, which is typically made of PVC
or polyurethane material. A yarn-like sleeve, typically made of
KEVLAR polymer, is often placed between the buffer and the jacket
to improve the tensile strength of the cable.
The growing use of fiber optic systems creates a need for a
connector capable of optically coupling a segment of fiber optic
cable to another optical device, such as an amplifier, diode or
other active component; a switch or other circuit; or another
segment of fiber optic cable. To achieve efficient light transfer,
the connector must align and space the optical elements, with or
without touching whichever is specified, with high precision. The
alignment and spacing requirements are exceedingly demanding, due
to the minute, micron-size diameter of the optical elements (e.g.,
fibers) being connected, coupled or otherwise terminated. During
light transmission through the coupled elements, it is essential to
maintain the precision alignment and spacing (or contact) of the
coupled elements, otherwise a signal interruption occurs, i.e. the
optical coupling deteriorates or fails.
One method of avoiding signal interruption is to design connectors
that screw together, or are otherwise permanently or
semi-permanently secured together. However, there is a need for
optical connectors that resist signal interruption and that also
allow quick connection and disconnection with mating
connectors.
One problem with known connectors of the quick connect and
disconnect type is that they are prone to inadvertent signal
interruption. One known optical connector which allows quick
connection and disconnection, and is marketed under the ST .RTM.
mark, has a captive bayonet nut for mating with a bayonet
receptacle, a body for supporting the optical fiber along an axis,
and a spring. The body has a front end which exposes a facet end of
the optical fiber for optical coupling with another optical
element. The spring serves two functions: it pushes the facet end
forward, towards the optical interface to maintain optical
connection, and it pushes the mating bayonet receptacle to maintain
the mechanical coupling of the two bayonet members.
If the back of this prior connector body, or its attached optical
cable, is pulled with a force sufficient to compress the spring,
the facet end is displaced axially backwards, away from the mating
optical element, and signal interruption occurs. A signal
interruption can also result from lateral forces applied on the
back of the connector and which displace the facet end of the
connector laterally, thus causing optical disconnect through fiber
misalignment.
Another problem with known quick connect and disconnect connectors
is that they provide only limited protection of the coupled optical
elements from corrosive agents in the operating environment. There
accordingly is a need for optical quick connect and disconnect
connectors that can operate in hostile environments, such as in the
presence of moisture or dust.
Accordingly, an object of this invention is to provide a fiber
optic connector that allows quick connection and disconnection with
ST.RTM. compatible and other optical connectors, and that resists
signal interruption, even when the connector or its associated
optical cable is stressed, either axially or laterally.
It is also an object of the invention to provide a fiber optic
connector that accommodates an environmental seal for sealing out
moisture, dust, and like contaminants.
These and other objects and features of the invention will be
apparent from the following description and the drawings.
SUMMARY OF THE INVENTION
A fiber optic connector according to the invention has a captive
element for mechanical coupling with a further optical connector,
and has an inner body, an outer body, and two resilient elements.
The connector can be quickly connected or disconnected to mating
optical connectors; and when connected, it resists signal
interruption even if the connector, or the associated optical
cable, is stressed.
The connector inner body has an axially extending through passage
for receiving and mounting an optical fiber with selected
alignment. The inner body has a front facet end for exposing a
facet of the optical fiber for optical coupling with another
optical element. The front facet end is at the front end of the
connector.
The connector outer body has two axially successive sections. A
first, rear section has an axially extending through channel for
receiving the inner body, so that the inner body can slide,
telescopically and axially, relative to the first section. The
first section also has a mechanism for securing the captive
element. A second section forms the front end of the outer body and
is arranged for axial displacement relative to the first
section.
The first resilient element biases the inner body axially forward,
relative to the outer body, to push the facet towards a mating
optical element.
The second resilient element biases the front end of the outer-body
second section forward relative to the first section.
In one preferred connector embodying the invention, the second
section of the outer body contacts a surface of the mating device,
typically an adapter or receptacle, when the connector is
mechanically coupled with the mating device.
The outer-body second section is, in one embodiment, slideably
mounted to the first section. The second resilient element is
disposed between the outer-body first and second sections to bias
the second section forward relative to the first section. The
second resilient element is normally under compression and pushes
the outer-body second section toward its maximum forward position.
When the connector is mechanically coupled with a mating device,
the outer-body second section is axially displaced rearward. This
displacement further compresses the second resilient element. The
compressive force exerted by the second resilient element is
transferred to the mating device to maintain the mechanical
coupling. In one embodiment, this resilient force maintains the
mechanical coupling because adaptor lugs of the mating device are
trapped by a bayonet slot of the captive element.
In another embodiment, the outer-body second section has a
resilient sleeve or collar-like structure fixed to the outer-body
first section. The outer-body second section compresses or deflects
axially when the connector is mechanically coupled with a mating
device, and the resiliency of the second section provides a
resilient force that maintains the mechanical coupling. In this
embodiment, the second resilient element is formed by the resilient
structure of the outer-body second section.
Other aspects of the invention will be more apparent from the
following description and the drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a longitudinal sectional view of a prior optical
connector of the quick connect and disconnect type mated with an
adaptor.
FIG. 2 is a longitudinal sectional view of a connector according to
the invention, separated from a mating adaptor.
FIG. 2A is a front end view of the connector of FIG. 2.
FIG. 2B is a rear end view of the connector of FIG. 2.
FIG. 2C is a top view showing the bayonette slot detail of the
connector of FIG. 2.
FIG. 2D is a transparent view of two mating components of the
connector of FIG. 2.
FIG. 3 is a sectional view of the connector of FIG. 2 at an
intermediate state of the process of mechanically coupling with a
mating adaptor.
FIG. 4 is a sectional view of the connector of FIG. 2 mated with an
adaptor.
FIG. 5 is a sectional view of a connector according to the
invention mated with an adaptor, and additionally showing an
environmental seal and an attached optical cable.
FIG. 6 is a longitudinal sectional view of another connector
according to the invention wherein the second section of the outer
body is fixed to the outer-body first section.
FIG. 7 is a sectional view of the connector of FIG. 6 connected
with a mating adaptor.
DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
FIG. 1 shows a prior quick connect and disconnect bayonet type
optical connector 10 mechanically coupled with a mating adaptor 22.
The connector has a body 13, a bayonet nut 16, and a spring 18. The
illustrated body 13 is fabricated with a ferrule 14 and a ferrule
holder 12. The body 13 supports an optical fiber along an axis 20
within a central passage extending throughout the length of the
connector. The optical fiber terminates at a front facet end 15 of
the ferrule 14. A spring 18 biases the body 13 forward (to the
right in the drawing) relative to the bayonet nut 16, so that the
facet end 15 is maintained at an optical interface 24. In practice,
the optical fiber is optically coupled to another optical element,
typically another optical fiber, located on the other side of
optical interface 24.
Mechanical coupling between the adaptor 22 and the connector 10 is
achieved when an adaptor lug 23 is trapped in a slot 17 in the
bayonet nut 16. In addition to providing a resilient force that
keeps the facet end 15 biased towards the optical interface 24, the
compressive force exerted by the spring 18 maintains the mechanical
coupling between the adaptor 22 and the connector 10 by maintaining
the adaptor lug 23 seated within the bayonet slot 17.
When the connector 10 is coupled with the adaptor 22, the body 13
is displaced rearwards (to the left in the drawing) from its
disconnected position. This displacement occurs because surfaces of
the adaptor (not shown) push on the facet end 15. The displacement
is such that there is normally a space between the surface 26 of
the body 13 and the opposed surface 28 of the adaptor 22.
The connector 10 of FIG. 1 can suffer from signal interruption if
the facet end 15 is inadvertently displaced rearwards, away from
the optical interface 24. Tension on the body 13 sufficient to
compress the spring 18 will cause this rearward displacement and
hence signal interruption. This tension typically results from
tension on the optical cable (not shown) attached to the back end
of the body 13. The connector 10 structure suffers from inadvertent
signal interruption because tension anywhere on the body 13, if it
is sufficient to compress the spring 18, is transferred to unwanted
motion of the facet end 15.
FIGS. 2, 2A, 2B, 2C, and 2D show a connector 30 according to the
invention and that is resistant to signal interruption. The
connector 30, shown in FIG. 2 disconnected from the adaptor 22, has
an inner body 43, an outer body 39, a bayonet-type coupling nut 36,
and two resilient elements 32 and 34. In the illustrated connector
30, these resilient elements are coil springs. As will be apparent
to those skilled in the art, other embodiments of the resilient
elements can be used, for example resilient element 32 can be a
bellows-like spring attached to the outer body 39.
The illustrated outer body 39 has a first section 38 and a second
section 40. The first section 38 has a tubular shape with an inner
passage 53 for receiving the inner body 43. The inner passage has
three axially successive cylindrical compartments 53A, 53B, and
53C, concentric with the axis 48 and each with a different
diameter. The middle compartment 53B houses the resilient element
32 which is located radially inner-wise relative to the other
resilient element 34, and the back end of which abuts a radial
shoulder 54 formed at the junction of the rear and middle
compartments of the inner passage. As shown in FIG. 2D, middle
compartment 53B has an inner hexagonal cut 38a at its forward end
to prevent rotation of ferrule holder 45, relative to first body
section 38, which has a corresponding outer hexagonal cut 45a. The
inner passage forward compartment 53C houses the resilient element
34. A shoulder 56 at the juncture of the middle and forward
compartments abuts a back end of the outer resilient element 34.
The forward end of the first body section 38 forms an opposing
shoulder 58. The outer surface of the first body section 38 traps
the bayonet nut 36 between two opposing radially grooved
shoulders.
With further reference to FIG. 2, 2A, 2B, 2C, and 2D, the second
section 40 of the illustrated connector outer body 39 is a
relatively short tubular collar, concentric with the axis 48 and
having a cylindrical inner passage that slideably receives the
ferrule 42 of the connector inner body 43. The second section 40
accordingly can slide axially relative to the first section 38. The
axial back end of the second body section has a flange 57 that is
slideably received within the forward passage compartment 53C of
the first body section 38. The shoulder 58 of the first body
section 38 traps the flange 57, to secure the second body section
40 to the first body section 38 and to limit the forward axial
movement of the second body section. Further, the front end of the
illustrated coil spring that forms the resilient element 34 is
compressively engaged between the shoulder 56 and the flange 57 to
resiliently urge the second body section 40 axially forward, to the
extreme forward position of FIG. 2, relative to the first body
section 38.
The inner body 43 of the illustrated connector 30 has a
cylindrically shaped ferrule 42 secured to a hex portion ferrule
holder 45, each concentric with axis 48. The hexagonal keying
section 45A of ferrule holder 45 slides within the corresponding
inner hexagonal middle compartment 53C of inner passage 53 and
prevents undesirable rotation of ferrule holder 45 relative to
first body section 38 of outer body 39. The inner body 43 supports
an optical fiber along the axis 48 within a passage 59 extending
from the rear of the inner body 43 to a front facet end 47 of the
ferrule 42. The illustrated passage 59 has a relatively large
diameter in the ferrule holder 45, to receive the buffer on a
cable, and has a relatively small precission diameter in the
ferrule, to receive and position an unbuffered fiber. The ferrule
holder 45 has a cylindrical rear stub 46 and a forward portion 44
with a larger diameter.
The ferrule holder 45 forms, at the juncture of the stub 46 and the
forward portion 44, a shoulder 55 that abuts a forward end of the
inner resilient element 32. A feeder tube 52 is typically attached
to the stub 46 and extends to the back of the outer-body first
section 38. The diameter of the feeder tube 52 is slightly smaller
than the diameter of the inner passage rear compartment of the
outer-body first section 38. The hexagonal width of the ferrule
holder hexagonal keying section 45A is slightly smaller than the
width of the corresponding inner hexagonal middle compartment 53C
of outer-body first section 38, thus allowing the inner body 43 to
slide axially within the outer-body 39. The ferrule 42 has a
smaller diameter than the inner diameter of the ferrule holder 45
forward portion 44. A shoulder 61 formed at the juncture of the
ferrule 42 and the forward portion 44 abuts the opposing shoulder
60 formed by the outer-body second section 40. The ferrule 42
projects concentrically through the central passage of the
outer-body second section 40.
The illustrated coil spring that forms the inner resilient element
32 is disposed within the inner cavity middle compartment 53B of
first section 38, between the axially opposed shoulders 54 and 55.
The resilient element 32 is normally under compression and exerts a
force which biases the inner body 43 forward relative to the
outer-body first section 38, thus pushing the facet end 47 of the
connector forward, towards an optical interface 50. Rearward motion
of the inner body 43 is resisted by the force exerted by the first
resilient element 32, and forward motion of the inner body 43 is
restricted by the abutment of shoulders 60 and 61.
With this structure of the connector 30, the inner body 43 can
translate axially relative to the outer body 39, and particularly
relative to the outer-body first section 38. This relative axial
movement is limited by interfering surfaces and is resiliently
biased by the inner resilient element 32. In addition, the
outer-body second section 40 can deflect axially relative to the
first section 38, under the resilient bias of the outer resilient
element 34 and limited by interfering surfaces.
With further reference to FIG. 2, the axial length of the inner
body 43, formed by the holder 45 and the ferrule 42, is sufficient
to secure an optical fiber to the connector and to position and
support it both axially and radially. The axial length of the outer
body 39 is sufficient to supportingly mount the holder 45 of the
inner body and to mount and confine the resilient elements 32 and
34. The back-most, first section 38 of the illustrated outer body
39 extends axially for the major portion of the overall outer-body
length, and the front-most second section 40 has considerably less
axial length.
With reference to FIG. 2, and in particular FIG. 2C, the structure
of the bayonet nut 36 is well known in the art, and has a bayonet
slot 37 for receiving and trapping adaptor lugs 23.
With reference to FIGS. 3 and 4, when the connector 30 is
mechanically coupled with the adaptor 22, a frontal surface 49 of
the outer-body second section 40 abuts a surface 28 of the adaptor
22. FIG. 3 shows the connector 30 in the process of being
mechanically coupled with the adaptor 22. The adaptor lug 23 is at
an intermediate position within the bayonet slot 37, the outer
resilient element 34 is maximally compressed, and the outer-body
second section 40 is displaced axially to its furthest rearward
position.
FIG. 4 shows the connector 30 fully coupled to the adaptor 22. The
outer-body second section 40 transfers the force exerted by the
resilient element 34 to the adaptor 22, and this force maintains
the mechanical coupling because the adaptor lug 23 is trapped by
the bayonet slot 37, as shown in FIG. 2C.
The connector 30 resists signal interruption because, when the
connector 30 is coupled to the adaptor 22, the outer-body first
section 38 and the bayonet-nut 36 it carries mechanically transfer
to the adaptor 22 tension exerted on the rear of the connector, or
its associated optical cable (not shown); the connector structure
in essence isolates the tension from the connector facet end 47 and
hence from the optical interface 50. The adaptor 22 and the
connector outer-body first section 38, with the bayonet nut 36,
when coupled together, form an optically rigid assembly, rather
than multiple pieces coupled by a spring which maintain optical
communication directly by tensional components. The connector facet
end 47 can displace axially backwards by backward displacement of
the inner body 43 relative to the outer-body first section 38 in
response to compressive engagement exerted on the other side
(rightmost in FIG. 4) of the optical interface to prevent damage or
crushing of the optical elements, but the facet end 47 does not
displace relative to the optical interface 50 in response to
tension on the exterior of the connector 10 or the adaptor 22.
As further shown in FIG. 2, a lateral force applied at the back of
the connector 30, i.e., in the direction of vector 70, produces an
opposite lateral motion at the facet end 47 in the direction of
vector 72. This -is true of prior connectors as well as the
connector 30 of the present invention. If the lateral motion at the
facet end is sufficiently large, signal interruption will result,
because the optical fiber will no longer be properly aligned with
the mating optical element at the optical interface 50. It is
common for connectors to suffer from this kind of signal
interruption if the forces are sufficiently large. However, the
connector 30 of the present invention provides improved performance
at resisting signal interruption in the presence of lateral forces.
The relatively rigid mechanical coupling of the outer-body first
section 38 to the bayonet nut 36 via contacting sleeve rings 71,
rather than by a spring as in the prior art, causes the connector
to be more resistant to misalignment from lateral forces. The
relatively small lateral play that is possible is compensated for
by the resiliently-biased support of the inner body.
FIG. 5 shows the connector 30 attached to an optical cable 80 that
has a buffer 87 surrounding the optical fiber 86, and a protective
jacket 82 covering the yarn-like sleeve 84.
The optical fiber 86 is secured to the inner body 43, typically
with adhesive material such as glue or epoxy within the inner body
43. In one preferred practice, the epoxy adhesive is injected into
the inner-body passage 59 with a syringe, and then the optical
fiber is inserted into the passage along the axis 48. The feeder
tube 52 functions as a barrier to prevent the adhesive from leaking
or spilling into other portions of the connector. After the
adhesive is applied, the connector 30 is assembled with the cable
80 by threading the fiber 86 into the ferrule 42 and inserting the
buffer 87 into the feeder tube 52 and through the ferrule holder 45
until it abuts the back of the ferrule 42. The cable jacket 82 is
stripped to expose a length of the buffer 87 such that when the
buffer 87 abuts the back of the ferrule 42, the jacket 82 abuts the
back end of the outer body 39. The yarn-like cable sleeve layer, if
present, can be pulled over the outer body 39. A crimp sleeve 88 is
then applied to span over both the optical cable 80 and the
outer-body first section of the connector 30. The outer-body first
section 38 preferably has a tapered edge 91 to assist applying the
crimp sleeve 88. The crimp sleeve 88 closes over the rear of the
outer body 39 and a portion of the jacket 82. The annular grooves
89 help captivate the crimp sleeve 88.
FIG. 5 also illustrates the provision of an optional environmental
seal in the connector 30, according to the invention. In this
embodiment, the connector outer body 39 carries an annularly shaped
seal 90 disposed over the outer-body second section 40. When the
connector 30 is mated with the adaptor 22, the seal 90 abuts a
radially-extending surface of adaptor 22. This contact forms an
environmental seal that seals out corrosive agents such as water,
dust and the like. It will now be apparent that the connector 30
can attain such a protective seal by providing an annular seal,
similar to the seal 90 of FIG. 5, on the adapter 22. That is, the
seal 90 of FIG. 5 can be provided on either the connector 30 or on
the adapter 22. It may also be advantageous to provide such seals
on both the connector and on the adapter.
FIG. 6 illustrates another connector 30' according to the
invention, in which the outer-body second section 40' has an
axially deflecting structure. This is in contrast to the rigid
collar-like structure of FIG. 2 which telescopically slides axially
relative to the outer-body first section 38. More particularly, the
illustrated connector 30' of FIG. 6 can be identical to the
connector 30 of FIG. 2, except that the outer-body second section
40' is fixedly secured at the forward end of the first section 38',
and is resiliently axially collapsible. To this end, the second
section 40' can employ a resilient compressive sleeve or,
alternatively, a bellows sleeve. The resiliency of the sleeve
provides the resilient force supplied by the outer spring element
34 of the FIG. 2 connector 30. The outer-body second section 40'
thus both forms part of the connector outer body 39 and constitutes
the outer resilient element 34 of FIG. 2 for the connector 30'.
Moreover, the resilient deflection of the outer-body second section
40' can provide a sealing engagement with the mated adapter 22,
thereby cooperating with or replacing the seal 90 of the FIG. 5
connector 30. FIG. 7 shows the connector 30' mechanically coupled
to the adaptor 22.
The forgoing description is merely illustrative and those skilled
in the art will understand other modifications to the described
device. Such the modifications and improvements are to be
encompassed within the scope of the following claims.
Further, the invention has been described with particular reference
to a connector of the quick connect and disconnect type. It will be
apparent to those skilled in the art that the structural connector
features which the invention provides can be advantageously used in
other types of connectors .
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